1. Field of the Invention
The present invention is generally directed to the field of electrical connectors, and, more particularly, to an electrical connector that may be employed in subsea applications and other wet environments.
2. Description of the Related Art
In many industries, electrical power is supplied to components positioned in a body of water. For example, in the oil and gas industry, power may be supplied to various components or devices positioned on the floor of the ocean. As a specific example, electrical power may be supplied to various valves and electrical instrumentation positioned on or adjacent a Christmas tree or blowout preventer positioned on a subsea wellhead. The power is typically supplied by a power generation unit or plant located on a surface vessel or on a drilling or production platform located above the surface of the ocean. In some cases, the power supply unit may be located on land adjacent the body of water.
Typically, an electrical connector is provided between the power supply unit and each of the subsea components so that, when desired, the power supply may be disconnected if needed. Electrical connectors employed with such subsea components are usually contact-based electrical connectors wherein a conductive electrical flow path is established through the connector halves by contact between one or more electrically conductive components in each connector half. Such contact-based electrical connectors are different from induction-based electrical connectors wherein the conductive flow path is established, at least in part, by the interaction between various electrical fields.
To date, contact-based electrical connectors employed in such wet environments suffer from several deficiencies and cause many problems. For example, with existing subsea contact-based connectors, the power supply must be shut off before mating or unmating the electrical connector. That is, with existing subsea contact-based connectors, the connection cannot be established or broken without shutting off the power supplied to the connector. If a connection is broken with electrical power on, these connectors tend to fail. Such deficiencies with existing subsea connectors cause many problems. In some applications, many such contact-based connectors are employed to provide electrical power to several components on various subsea systems and installations. Such systems may be very complex and, once they reach an operational state, it is undesirable to shut off power to all or substantially all of the system when it is necessary to connect/disconnect power to a particular subsea component.
Troubleshooting various problems is also difficult due to the inability of subsea contact-based connectors to be mated/unmated with the power supply on. For example, if a particular downhole component malfunctions or completely stops working, it may be difficult to determine if the cause of the failure is due, in whole or in part, to the electrical power supplied to the malfunctioning component or other components. In a typical system installed on land, part of the troubleshooting process might involve mating/unmating various electrical connectors that supply power to various components of the land-based system. This mating/unmating process may provide useful information as it relates to determining potential causes of the failure or malfunction and/or eliminating potential causes of the failure or malfunction.
With subsea contact-based connectors, where the electrical connections may not be readily established and broken with the power supply “on,” i.e., when the connections are “hot,” operating personnel may undertake additional actions as it relates to troubleshooting problems. For example, engineers may review many electrical power schematics in an effort to determine potential causes of the failure. Such a procedure can be very time consuming and somewhat inefficient as it is a less direct method of investigating some problems encountered in many failure situations.
Induction-based connectors also suffer from several deficiencies as it relates to their use in subsea applications. In general, such induction-based connectors have not met the high degree of reliability desired for subsea equipment applications. Moreover, the physical size and expense of such induction-based electrical connectors are drawbacks to their widespread implementation in subsea applications.
The present invention is directed to various devices and methods for solving, or at least reducing the effects of, some or all of the aforementioned problems.